If you’re an online retailer with a mobile-friendly website, you’re going to reap even more benefits.

In fact, if you can make mobile checkout easier, online retailers can increase their total holiday season revenue by 7.3 percent.

Here’s another astonishing fact to digest: Sales made on smartphones hold a $9 billion potential for retailers this season, or the equivalent to earning a second Cyber Monday. Shoppers using smartphones are expected to drive close to one-third of the total revenue of online purchases this year.